Posted by Jack Vamvas on 03/04/07 09:36

Assuming you aren't repeating data in TRANSPORTATION_ITEM then you are
already satisfying one of the normalisation principles.i.e minimising
redundancy.
Even though what you are doing in TRANSPORTATION_ITEM will work, I would
separate into 2 tables with distinctive names for the tables.


--

Jack Vamvas
___________________________________
The latest IT jobs - www.ITjobfeed.com
<a href="http://www.itjobfeed.com">UK IT Jobs</a>


<bbcrock@gmail.com> wrote in message
news:1172984454.273489.90110@s48g2000cws.googlegroups.com...
>I have three tables with a relationship I've never worked with
> before. Can anyone suggest/comment on the best way to create a third
> normal form relationship between these tables?
>
> The tables basically are:
>
> TRAIN (TRAIN_ID and 15 columns about train specs, etc)
> TRUCK (TRUCK_ID and 12 columns about truck specs, etc)
> TRANSPORTATION_ITEM
> This table has, among others, two columns, TRUCK_ID and TRAIN_ID. If
> the truck column is used there can be no data in the train column and
> vice versa.
>
> This relationship seems denormalized to me, but I don't remember how
> to normalize it. Does anyone know the correct name for this kind of
> relationship?
>
> thanks!
>

[Back to original message]